1. Preheat oven to 350°. Coat a skillet with olive oil cooking spray; set on medium-high heat. Slice polenta into a dozen 1/2-inch-thick rounds. Toast slices in skillet until golden brown, 4-5 minutes on each side.

2. Place slices in an 8x8-inch baking dish lightly coated with cooking spray (overlap a couple of slices, if necessary). Cover with marinara sauce and sprinkle with spices, to taste. Top with grated cheeses. Sprinkle with olives, if using. Bake for 20-25 minutes or until hot and bubbly.